James steven wyndham and john harry hallett



(No Model.)

J. s. WYNDHAM & J. HQHALLETT. GHEUK VALVE- No. 74,295. Patented Dec. 29,1896.

UNITED 1 STATES PATENT OFFICE.

JAMES STEVEN WYNDHAM AND JOHN HARRY HALLETT, OF CARDIFF, ENGLAND.

CH EC K'-VALVE.

SPECIFICATION forming part of Letters Patent No. 574,295, dated December29, 1896.

Application filed January 24, 1896. gerial 110,576,714. (No model.)Patented in England November 18, 1895, ITO. 21,922,

' and November 22, 1895,110. 22,358.

1895, and No. 22,358, dated November 22,

1895;) and we do hereby declare that the following is a full, clear, andexact description of the invention, reference being made to theaccompanying drawings, which are to be taken as part of thisspecification and read therewith, and one which will enable othersskilled in the art to which it appertains to make and use the same.

This invention relates to improvements in check-valves such as are usedon the watersupplies to steam-boilers and to which it is particularlyapplicable.

It is the common experience of engineers that the valve ordinarily usedas a checkvalve on water-supplies to steam-boilers gets out of workingorder very quickly, because at the end of each lift the crown of thevalve hammers violently against the stop, and also because the valvebeats itself heavily on the miter or seat at the end of each drop of thevalve.

The object of the present invention is to prevent the above-mentionedhammering and heating.

The invention includes improved means for providing for the presence ofa watercushion between the valve-face and its seating during the drop ofthe valve.

It also includes improved means for providing for the presence of awater-cushion between the back of the valve and the valvestop during thelift of the valve.

It further includes the combination, with the valve, valve-seat, andvalve-stop, of improved means for providing for the presence of awater-cushion between the valve-face and its seating during the drop ofthe valve and for the presence of a water-cushion between the valve andthe valve-stop during the lift of the valve.

Referring to the accompanying drawings, F gure 1 is a vertical sectionthrough the center of an ordinary check-valve box fitted with ourimproved valve-guard and spindle. Fig. 2 is a vertical section of amodification of the present invention.

' Referring to Fig. 1, A is the flange by which the valve-box is held tothe boiler or to the pipes. B is the flange by which the lower part ofthe said box is held to the feed-pump pipe. 0 is the cover of thevalve-box, and c the stufling-box therein. The foregoing parts are ofthe same construction as heretofore.

D is the valve seat or miter, and E the flange outside the same.

F is the improved valve; F, its miter; f, its lip, extending round theouter edge of it, and G a central annular cavity in the back of thevalve formed by the lipsf being in a plane higher than that of the valveF. The miters D and F being the actual valve-seat and the contactingvalve-surface, respectively, are,as far as they themselves areconcerned, the same as heretofore. The lipf stands in such a positionrelatively to the flange E that when the latter is on its seat or miterD the under face of the lip is separated from the flange E by a distanceH.

I is the bottom end of the screwed spindle J and forms the valve-stop.The spindle is tubular throughout its length. The valvestop I is in theform of an inverted cup having a large horizontal rim i. The cavityt' ofthe valve-stop I corresponds in respect of its contour with that of thecrown f of the valve F, while the cross-section of the rim t'corresponds with that of the cavity G.

j is the screw-thread on the tubular spindle J. It engages in thedepending extension L of the cover 0. The spindle passes out through thestuffing-box c for a sufficient distance, and is there fitted with ahand-wheel R for adjusting the lift of the valve F or for holding itdown upon its seat, according to the distance at which the end I is setover such valve. The stop I stands at a suliicient distance above thevalve F to allow of its maximum lift.

K is a collar on the spindle J, adapted by its position thereon to limitthe upward motion of the said spindle by contacting with the oppositeend of the extension L. It also serves, when screwed up tight againstthe latter, to form a water and steam tight closure between thestuffing-box c and the interior of the valve-box, thereby relieving thestuffing-box from steam-pressure.

R is the usual hand-wheel, fast on the outer end of the spindle J forturning it.

N is the valve-spindle, fast to and projectin g upward from the crown fof the valve F and entering the bore of the spindle J, whereby theaccurate motion of the valve F is secured.

O is a set-screw adapted to work up and down the screw-thread 0 in thetop end of the spindle J, and o is a nut for locking it in any desiredposition therein.

P is a spiral spring within the tube J and between the spindle N and theset-screw O. This spring is sufliciently strong to, usingthe inner endof the set-screw O as a base, keep the valve F down upon its seatindependently of the pressure upon the back of the latter.

Our invention operates in respect of its several features as follows:

T Vatcrcushion during thedrop of he wire-The improved means forproviding this consists of the lip f, the flange E, and the spring P. Atthe moment when the valve begins its drop under the action of the saidspring there is obviously an annulus of water between the said lip andflangefand E. The whole of this annulus, with the exception of as muchas is represented by the space H, must be displaced by the spring Pbefore the valve F can reach its seat. It is the yielding resistance ofthe above-mentioned annulus of water to the action of the spring P thatconstitutes the water-cushion in question, such yielding being delayedby the opposition to the motion of the water away from the axis of thevalve due to the presence of the opposite portion ofthe valve-box.

Water-cushion du ring the lift ofthe value. The improved means forproviding this consists, according to one modification of the invention,of the lip f, the cavity G in the back of the valve, the rim ion thevalve-stop I immediately above the said cavity, the valvecrown f, andthe cavity t" in the valve-stop immediately above the said crown. At themoment when the lift of the valve F commences there is obviously anannulus of water between the valve back and crown beneath and thestop-rim t' and cavity 2" above. The whole of this annulus must beremoved before the lift can be completed, and it is its yieldingresistance to the suction acting on the under side of the valve thatconstitutes the water-cushion in question, such yielding being delayedby the opposition to the motion of the water away from the axis of thevalvespindle N due to the presence of the inner edge of the lip f andthe cup According to the other modification of the inventiontl1e oneillustrated in Fig. 2-the central annular cavity G and the rim 2' aredispensed with and both valve-crown j and cup-shaped cavity 2" enlargedaccordingly.

We claim- The combination of mitercd valve-scat, a flange outside thesame in the plane of the top of it, a mitered valve, a lip outside thesame and projecting therefrom in a plane sufiiciently high to stand at adistance above and clear of the top of the above-mentioned valve-seatflange when the valve is down on its seat, a spindle standing up fromthe center of the back of the valve, a tubular spindle adapted toreceive the said spindle, an annular cavity in the back of the valvebetween the crown and the lip of the flange and an adjustable valve-stopof the same diame ter as the said annular cavity and presenting acorresponding sectional contour to the said annular cavity and crown.

In witness whereof we have hereunto affixed our signatures, in presenceof two witnesses, this 10th day of January, 1806.

JAMES STEVEN IVYNDHAM. JOHN HARRY I-IALLETT.

Witnesses SAMUEL WEsLnv ALLEN, G. ED. WAueHrLnve.

